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Birdwhales
The great blue blorca, which feeds on plankton in the cold northern and southern seas, is one of the largest filter-feeding birdwhales, just over fifty feet in length. ~~~ Cetaforme pelecanaries, colloquially known as "birdwhales", are very large, entirely aquatic pelecanaries which occur in abundance across all of Serina's seas by the Cryocene. A group which includes the bloon, it's a highly diverse clade with representatives that fill many different niches, all tied together by their mouth-brooding behavior. By incubating their single large eggs in their throat pouches rather than on land, all birdwhales have cut their ties to the shore, freeing some to become the largest birds ever to live. Whereas the basal bloon is an herbivore, most birdwhales are predatory and eat either fish, plankton, or other aquatic invertebrates. Forms are specialized as pursuit hunters, bottom-feeders, and filter-feeders, the latter being among the most specialized. Birdwhales use large paddle-shaped wings to swim through the water, sometimes also using their hind legs to assist while in other groups the hind limbs are fused into a rudder-like tail. They are almost totally featherless with smooth skin and keep warm with insulating layers of body fat. Fish-eating birdwhales often exhibit large pseudotheeth in their bills to hold onto their prey, while planktonivores have wide-gaping mouths and gigantic throat pouches to scoop up huge mouthfuls of seawater. While taking in food, the tongue is lifted to the roof of the mouth, blocking water from going down the throat into the stomach or airways. The tongue is then brought down and the water is strained out of the mouth through hair-like cillia which have formed on its edges, producing a seining net that catches any small fish or invertebrates which are then consumed. Some filter feeders specialize on small fish while others target Serinan "krill" - any variety of free-swimming crustaceans, from copepods and shrimp to crab larvae. Some birdwhales feed by filtering the sediment on the sea floor. While most filter-feeding birdwhales are very large animals, they are not on the whole as large as the biggest whales on Earth. The very longest birdwhale species, in fact, is not a filter feeder at all - it is the bloon, a vegetarian of coastal waters. Filter-feeders are most abundant in the cold polar seas near Serina's poles, where the waters are rich in nutrients. The calves are born large and able to swim and feed themselves at birth, but require their parents' guidance to find food and avoid predators; they stay with their parents for many years before becoming independent. Birdwhales mate for life, almost always being found in pairs at the minimum, with some species living in large extended families. If lucky, the largest birdwhales can live for more than two hundred years. = dolfinch = a dolfinch - a fully marine live-bearing canary of Serina's Pangeacene era 228 million years after the introduction of the first canaries, glides just beneath the surface of the sea under the soft light of the gas giant. Though it can be easy to forget, Serina - even inhabited as it is with life - is a moon and not a planet. It revolves around a far larger celestial body: a bluish colored gas giant which appears as a large "moon" in its own sky, several times larger than our own appears from Earth and easily spotted either day or night. As Serina rotates at an angle along its axis, its planet is not always present in the sky, but when the moon's surface does face it the planet is prominent and unmistakable - and as would be expected, its presence has a very dramatic effect on the world of birds. So large and bright is the light blue celestial body that when it appears at night - which it does roughly half of the time as Serina simultaneously orbits it and rotates on its own axis - when the skies are clear and free of clouds, it illuminates the environment as if a blue floodlight has been cast over the land. The light reflected by the gas giant from the sun which it orbits - and as a result Serina orbits as well - can then be sufficiently bright that diurnal birds continue to call and feed and even the dead of night is bathed in a state of blue twilight, where the normal partitions of day and night life are broken and nocturnal and diurnal animals come out together.. Conversely, when the planet's reflected sunlight is hidden from view on the other side of the moon, the night - particularly under cloud cover - can be pitch black. It is then that the less specialized daylight lifeforms retire and the nocturnal organisms emerge to feed with the greatest ease. Serina rotates around its planet in an elliptical manner, and thus is at times nearer and further from the gas giant's gravitational pull, which is the source of Serina's tides. Oceanic tides are generally stronger than those of Earth, and richly diverse floodplain ecosystems occur abundantly along the sea coasts as a result of a daily reliable surge of water inland. = The Emperor Bloon = Male Emperor Bloon, Partuphagus imperialis (from the Latin "Partus", meaning childbirth, and "Phagus", meaning to consume.) ~~~ Fifty million years have passed on the small green moon of Serina since the first canaries were set free upon the land. In these long intervening years, a world was built from the barest of foundations to a diverse pallet of life today unmatched anywhere in the cosmos. The descendants of Serina's very earliest songbirds have today conquered land, air, and sea, filling an ecological vacuum in a world without other tetrapods to compete with in ways that our own world has never known. One of the most specialized lineages birds of Serina fifty-million years PE are the Bloons. Growing to more than sixty feet (18 meters) in length and weighing up to fifteen thousand pounds (6800 kg) they are a family of gentle, herbivorous leviathans which make their existences as Serina's analog to sea cows across the moons' tropical seas, where they graze upon immense undersea meadows of kelp and sea grass, eating up to a thousand pounds of it in a days' time. Several times too heavy to leave the water and with their hind limbs all but vestigial, fused to their pygostyles, these easy-going, wing-powered swimmers spend their entire lives at sea, from hatching to death. This is possible because while like all birds so far to evolve at this time, the bloons must lay hard-shelled calcified eggs - eggs that cannot survive prolonged immersion in seawater - they belong to an ingenious order of sea birds which have found a unique and exceptional method of caring for their eggs which requires no visitation to the shore in the form of mouth-brooding. ~~~ Mouth-brooding - at its simplest meaning to protect the eggs or young from predators by hiding them in the mouth, is a relatively common behavior in many fishes and even some tetrapods. The reproductive behavior of the bloons however marks a first in birds; in these species and their relatives, it exists as a highly-derived behavior originating from an ancestral tendency to protect the young chicks from danger or keep them warm by carrying and holding them in a pouch below the bill which likely first appeared more than thirty million years ago in the bloons' pelican-like ancestors. Once this was well-established over time, it was not a large step to also hold the eggs themselves there, for being able to transport ones' unhatched young - which virtually no other bird is known to do, even though the behavior is commonplace in mammals and even crocodillians - proved a highly beneficial behavior for a large seabird which nested increasingly far from land and upon less and less stable mats of plant material in the manner of a grebe, pushed from more choice breeding locations ashore by rampant predators and competitors on the world of birds. With eggs in this situation likely to roll into the water at the slightest mishap, evolution favored those eggs both most tolerant to brief immersion, with large and buoyant air pockets and waxy eggshell cuticles less easily permeated by seawater and behaviorally, those birds which as breeding adults would still recognize their own eggs outside the perimeter of a chosen nest - which very few birds today can - and further, which were both willing and able to return lost eggs to the nest if they were to fall out. As this novel egg retrieval behavior developed, and the parent bird's mouth evolved to be increasingly well-suited to the transport of both eggs and young - and furthermore, as one group of pouched piscivores became too large and ungainly to easily sit upon any manner of floating nest - they began to incubate their single eggs directly upon their own soft, feathered backs. By taking turns to transfer the egg between them and covering it by turning the head over their shoulder and inverting the warm, soft skin of the throat pouch over-top this home-grown "nest", they found a new way to provide the developing eggs with safety, warmth and humidity independent of any true nest site at all. This was effective, but for the most part required the protection of colonial breeding in isolated calm, shallow waters to truly work out, and so from here it was not long before one group was to eventually forego the use of any nest entirely and begin to hold the eggs directly within the confines of this specialized throat pouch at all times, the organ having over time evolved to become watertight and independent of the digestive system and the rest of the gizzard. This freed the adults to move freely whilst incubating and more importantly hid the vulnerable egg from predators entirely - factors which together allowed the birds to develop secondarily less colony-dependent lifestyles and to subsequently diversify greatly. Now the male simply plucked the floating eggs from the water as the female dropped them and maneuvered them safely and quickly into the specialized organ within his crop to incubate while still allowing him to feed himself and keep alert for predators. The egg became increasingly large - in some modern bloons it now approaches twenty pounds in weight - and insulated by the fat and tissue of the neck it is effectively impossible to crack, for a strong enough blow to rupture it would also break the adults' neck. Oxygenated every time the adult surfaced to breathe, kept warm and moist within the adult's body, in this way the bloons' ancestors developed a roundabout way to nurture their developing young within the safety of their bodies and to circumvent the formerly universal avian need to tend a nest on dry land. When the chick hatches after just a few months, it can swim and feed itself from birth, but remains close by its parents for several years, generally protected by merit of their great size and highly protective nature. Adults can rear as many as three clutches in a year and as chicks do not immediately disperse may be seen to be watching clutches as many as six or sometimes more young of various ages at one time. For additional protection, adults frequently form creches with other adults of several dozen or more young, guarding them as a herd from a myriad of predators which may lurk the shallow coastal seas that the gentle giants roam in hopes of picking off a straggler similarly to many earth waterbirds. Herds of bloons are rarely organized but individual pairs mate for life and good feeding grounds can attract loosely-associated gatherings of hundreds or rarely thousands of the animals along especially fertile coastlines. ~~~ Bloons are the most specialized member of their order at this period in time, having traded their piscivorous tendencies for a diet of green plants and algae and rarely slow-moving invertebrates, all managed by a goose-like serrated bill. Most of their relatives retain a more carnivorous diet, with diets ranging from small fishes and marine invertebrates up to large seabirds and even bloons themselves. Though they may differ greatly in appearance, size, and lifestyle, however, they can all be allied by their unique manner of internal incubation. In the bloons, this is done entirely by the male, but in smaller carnivorous species it is often a joint affair, with pairs regularly transferring the precious cargo between them every few days to feed whilst the other parent rests near the surface so as to create a calm and stable environment for its developing young. With a more active lifestyle, which in a predator often requires fast maneuvering and diving to deep depths, the risk of cracking or damaging the embryo within its pouch is too high to allow these animals to feed whilst also carrying the egg as the more sedate, plant-eating bloons - which never dive more than a few meters below their clear tropical waters - have the luxury to do. Modern bloons have almost wholly lost their plumage and retain only a very thin layer of fuzz over their bodies, generally just a few millimeters in length. Too large and bulky to properly preen, they are instead insulated by their body fat. ~~~ This was produced for a contest on Speculative Evolution forums concerning the evolution of aquatic organisms, but it is canon in the Serina project. By Sheather888 Category:Serina Category:Fandom Category:Birds